package com.example.a14874.imageswitching;

import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {
    private ImageView iDog;
    private Button Changebtn;
    private int[] dogImgs = {R.drawable.dog1,R.drawable.dog2,R.drawable.dog3,R.drawable.dog4,R.drawable.dog5,};
    private int index = 0;
    private Handler handler;
    private Boolean isPause = true;
    private final int MSG_CHANGE_DOG = 1001;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        iDog = findViewById(R.id.img_dog);
        Changebtn = findViewById(R.id.next);
        handler= new Handler(new Handler.Callback() {
            @Override
            public boolean handleMessage(Message message) {
                if(message.what == MSG_CHANGE_DOG){
                    index = (index+1)%dogImgs.length;
                    iDog.setImageResource(dogImgs[index]);
                    return true;
                }
                return false;
            }
        });
        new Thread(new Runnable() {
            @Override
            public void run() {
                while(true){
                    try{
                        Thread.sleep(200);
                    }
                    catch (InterruptedException e){
                        e.printStackTrace();
                    }
                    if(!isPause){
                        Message message = new Message();
                        message.what = MSG_CHANGE_DOG;
                        handler.sendMessage(message);
                        Log.e("MainActity", "send  change message");
                    }
                }
            }
        }).start();
        Changebtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                isPause = !isPause;
            }
        });
    }
}
